Summary/Abstract Problem of painful inflammatory diseases: Persistent or inappropriate inflammation underlies a broad range of painful diseases including musculoskeletal conditions, wounds and burns. Much of the pain associated with these diseases is due to the release of nociceptive mediators from leukocytes at the site of inflammation. Though treatments such as NSAIDs (Non-Steroidal Anti-inflammatory Drugs) are available, they are often inadequate due to limited efficacy and undesirable side effects. Vapogenix (VPX) is a clinical-stage pharmaceutical company specializing in developing a novel class of locally acting non- narcotic analgesics based on new uses, formulations and routes of administration of already approved volatile anesthetics (VAs), particularly topical application to treat localized pain. Current knowledge: VPX and others have demonstrated anti-nociceptive activity of VAs when applied topically. Some VAs have also been shown to have anti-inflammatory effects, both in vivo and in vitro. Recent publications suggest that this anti-inflammatory effect may be due to allosteric inhibition of integrin function, specifically ?L?2 and ?M?2 integrins. Activated ?2 integrins are known to be key players in inflammation, particularly by facilitating leukocyte migration to the damaged tissue. Hypothesis: Our hypothesis is that topical VAs have a dual benefit, combining anti-nociceptive and anti-inflammatory effects, and may reduce inflammation and associated pain through direct interactions with integrins. Aims: The overall aim of the proposed SBIR Phase I study is to identify the most promising VA for future development as a novel anti- inflammatory product for topical application in painful inflammatory conditions. This will be accomplished by establishing the pharmacological profile of VA interactions with integrins and by characterizing the functional effects using in vitro assays (Specific Aim 1), and also by demonstrating anti-inflammatory effects of locally administered VAs in vivo using a mouse model of acute inflammation (Specific Aim 2). Methods: Specific Aim 1 will be achieved by testing the interactions of six VAs with a panel of integrins using cell adhesion assays and by studying further these interactions using cell signaling and cell migration assays. For Specific Aim 2, two VAs will be tested in the mouse air pouch model for their ability to reduce inflammation when applied topically and when injected at the site of inflammation. Assessments will include total and differential cell counts and cytokine profiling. Long term objectives: The overall goal of this program, and a possible SBIR Phase II proposal, is the development of a novel topical formulation of a VA to treat painful inflammatory conditions. The final product will have dual anti-inflammatory and anti- nociceptive effects, and a topical application will provide a good safety profile. Inflammatory painful conditions affect millions of Americans and no ideal treatment is available, therefore the clinical need and the commercial opportunity associated with funding this effort is substantial.